We spent 3 nights during new years eve in the Bellagio while our extended family chose to stay in a more expensive hotel across the street. The Bellagio, tucked in between some taller hotels, was an excellent choice. The breakfast was amazing (really can't say enough about the variety of food provided or the service of the personnel working in the restaurant) and the service was friendly and helpful with everything. The rooms had internet (not wireless so take a cable) that was fast enough for us to skype home to family and friends. The rooms were spacious and clean. The bathroom was large with a nice bath/shower and plenty of hot water. If you don't take a laptop with you, they have an internet room downstairs but it's very pricey.
The rooms have a safe ("cofre"), which in our case, was locked open. We called reception and within minutes someone was sent to fix the problem.
The hotel is across the street from a beach, albeit of the two main beaches in São Luis, ours was the more poluted one. There were a number of excellent restaurants in the area, and cabs were plentiful. We were able to make it to historic São Luiz for 15 Reais. If you have a car, the hotel has a limited amount of gated parking. You may have to park on the street though if you don't get back very early.
I should note that during our stay the manager of a small shop 2 doors down from our hotel was murdered during a robbery. São Luis is a fairly violent city, with a reported 4000 murders in 2007. However if you're careful and don't wander around alone at night, you will be fine. My wife is brazilian and kept telling me to be careful. I never saw any violence so I didn't take it seriously until we were told about the shop owner.
I would definitely stay at this hotel again. A great price, yet within a stones throw of many of the higher priced hotels.
Unique Quality: Exceptional service; very friendly and polite personnel.